<template>
  <div class="full-calendar-body">
    <div class="weeks">
      <strong v-for="week in weekNames" class="week">{{ week }}</strong>
    </div>
    <div ref="dates" class="dates">
      <div class="dates-bg">
        <div v-for="week in currentDates" class="week-row">
          <div v-for="day in week" class="day-cell" :class="{ today: day.isToday, 'not-cur-month': !day.isCurMonth }">
            <p class="day-number">{{ day.monthDay }}</p>
          </div>
        </div>
      </div>

      <!-- absolute so we can make dynamic td -->
      <div class="dates-events">
        <div v-for="week in currentDates" class="events-week">
          <div
            v-for="day in week"
            class="events-day"
            track-by="$index"
            :class="{ today: day.isToday, 'not-cur-month': !day.isCurMonth }"
            @click.stop="dayClick(day.date, $event)"
          >
            <p class="day-number">{{ day.monthDay }}</p>
            <div class="event-box">
              <p
                v-for="event in day.events"
                v-show="event.cellIndex <= eventLimit"
                class="event-item"
                :class="[
                  classNames(event.cssClass),
                  {
                    'is-start': isStart(event.start, day.date),
                    'is-end': isEnd(event.end, day.date),
                    'is-opacity': !event.isShow
                  }
                ]"
                @click="eventClick(event, $event)"
              >
                {{ isBegin(event, day.date, day.weekDay) }}
              </p>
              <p v-if="day.events.length > eventLimit" class="more-link" @click.stop="selectThisDay(day, $event)">
                共{{ day.events.length - getEventsLength(day.events) }} 条
              </p>
            </div>
          </div>
        </div>
      </div>

      <!-- full events when click show more -->
      <div v-show="showMore" class="more-events" :style="{ left: morePos.left + 'px', top: morePos.top + 'px' }">
        <div class="more-header">
          <span class="title">{{ moreTitle(selectDay.date) }}</span>
          <span class="close" @click.stop="showMore = false">x</span>
        </div>
        <div class="more-body">
          <ul class="body-list">
            <li v-for="event in selectDay.events" v-show="event.isShow" class="body-item" @click="eventClick(event, $event)">
              {{ event.content ? event.content : event.title }}
            </li>
          </ul>
        </div>
      </div>

      <slot name="body-card"> </slot>
    </div>
  </div>
</template>
<script type="text/babel">
import dateFunc from './dateFunc'

export default {
  props: {
    currentDate: {},
    events: {},
    weekNames: {
      type: Array,
      default: []
    },
    monthNames: {},
    firstDay: {}
  },
  data() {
    return {
      // weekNames : DAY_NAMES,
      weekNamesMore: ['周日', '周一', '周二', '周三', '周四', '周五', '周六'],
      weekMask: [1, 2, 3, 4, 5, 6, 7],
      // events : [],
      isLismit: true,
      eventLimit: 3,
      showMore: false,
      morePos: {
        top: 0,
        left: 0
      },
      selectDay: {}
    }
  },
  computed: {
    currentDates() {
      return this.getCalendar()
    }
  },
  watch: {
    weekNames(val) {
      //   console.log('watch weekNames', val)
    }
  },
  created() {
    this.events.forEach((item, index) => {
      item._id = item.id || index
      item.end = item.end || item.start
    })
    // this.events = events
  },
  methods: {
    getEventsLength(events) {
      const arr = []
      events.forEach((item, index) => {
        if (item.isShow == false) {
          arr.push(item)
        }
      }, this)
      return arr.length
    },
    isBegin(event, date, index) {
      const st = new Date(event.start)

      if (index == 0 || st.toDateString() == date.toDateString()) {
        return event.title
      }
      return '　'
    },
    moreTitle(date) {
      const dt = new Date(date)
      return this.weekNamesMore[dt.getDay()] + ', ' + this.monthNames[dt.getMonth()] + dt.getDate() + '日'
    },
    classNames(cssClass) {
      if (!cssClass) return ''
      // string
      if (typeof cssClass === 'string') return cssClass

      // Array
      if (Array.isArray(cssClass)) return cssClass.join(' ')

      // else
      return ''
    },
    getCalendar() {
      // calculate 2d-array of each month
      // first day of this month
      const now = new Date() // today
      const current = new Date(this.currentDate)

      const startDate = dateFunc.getStartDate(current) // 1st day of this month

      const curWeekDay = startDate.getDay()

      // begin date of this table may be some day of last month
      let diff = parseInt(this.firstDay) - curWeekDay
      diff = diff > 0 ? diff - 7 : diff

      startDate.setDate(startDate.getDate() + diff)
      const calendar = []

      for (let perWeek = 0; perWeek < 6; perWeek++) {
        const week = []

        for (let perDay = 0; perDay < 7; perDay++) {
          week.push({
            monthDay: startDate.getDate(),
            isToday: now.toDateString() == startDate.toDateString(),
            isCurMonth: startDate.getMonth() == current.getMonth(),
            weekDay: perDay,
            date: new Date(startDate),
            events: this.slotEvents(startDate)
          })

          startDate.setDate(startDate.getDate() + 1)
          // if (startDate.toDateString() == endDate.toDateString()) {
          //   isFinal = true
          //   break
          // }
        }
        calendar.push(week)
        // if (isFinal) break
      }
      return calendar
    },
    slotEvents(date) {
      // find all events start from this date
      const cellIndexArr = []
      const thisDayEvents = this.events.filter(day => {
        const dt = new Date(day.start)
        const st = new Date(dt.getFullYear(), dt.getMonth(), dt.getDate())
        const ed = day.end ? new Date(day.end) : st
        // console.log('slotEvt', st, ed, date)
        return date >= st && date <= ed
      })

      // sort by duration
      thisDayEvents.sort((a, b) => {
        if (!a.cellIndex) return 1
        if (!b.cellIndex) return -1
        return a.cellIndex - b.cellIndex
      })

      // mark cellIndex and place holder
      for (let i = 0; i < thisDayEvents.length; i++) {
        thisDayEvents[i].cellIndex = thisDayEvents[i].cellIndex || i + 1
        thisDayEvents[i].isShow = true
        if (thisDayEvents[i].cellIndex == i + 1 || i > 2) continue
        thisDayEvents.splice(i, 0, {
          title: 'holder',
          cellIndex: i + 1,
          start: dateFunc.format(date, 'yyyy-MM-dd'),
          end: dateFunc.format(date, 'yyyy-MM-dd'),
          isShow: false
        })
      }

      return thisDayEvents
    },
    isStart(eventDate, date) {
      const st = new Date(eventDate)
      return st.toDateString() == date.toDateString()
    },
    isEnd(eventDate, date) {
      const ed = new Date(eventDate)
      return ed.toDateString() == date.toDateString()
    },
    selectThisDay(day, jsEvent) {
      this.selectDay = day
      this.showMore = true
      this.morePos = this.computePos(event.target)
      this.morePos.top -= 100
      const events = day.events.filter(item => {
        return item.isShow == true
      })
      this.$emit('moreclick', day.date, events, jsEvent)
    },
    computePos(target) {
      const eventRect = target.getBoundingClientRect()
      const pageRect = this.$refs.dates.getBoundingClientRect()
      return {
        left: eventRect.left - pageRect.left,
        top: eventRect.top + eventRect.height - pageRect.top
      }
    },
    dayClick(day, jsEvent) {
      this.$emit('dayclick', day, jsEvent)
    },
    eventClick(event, jsEvent) {
      if (!event.isShow) {
        return
      }
      jsEvent.stopPropagation()
      const pos = this.computePos(jsEvent.target)
      this.$emit('eventclick', event, jsEvent, pos)
    }
  }
}
</script>
<style lang="scss">
.full-calendar-body {
  margin-top: 20px;
  .weeks {
    display: flex;
    border-top: 1px solid #e0e0e0;
    border-bottom: 1px solid #e0e0e0;
    border-left: 1px solid #e0e0e0;
    .week {
      flex: 1;
      text-align: center;
      border-right: 1px solid #e0e0e0;
    }
  }
  .dates {
    position: relative;
    .week-row {
      // width: 100%;
      // position:absolute;
      border-left: 1px solid #e0e0e0;
      display: flex;
      .day-cell {
        flex: 1;
        min-height: 100px;
        padding: 4px;
        border-right: 1px solid #e0e0e0;
        border-bottom: 1px solid #e0e0e0;
        .day-number {
          text-align: right;
        }
        &.today {
          background-color: #fcf8e3;
        }
        &.not-cur-month {
          .day-number {
            color: rgba(0, 0, 0, 0.24);
          }
        }
      }
    }
    .dates-events {
      position: absolute;
      top: 0;
      left: 0;
      z-index: 1;
      width: 100%;
      .events-week {
        display: flex;
        .events-day {
          cursor: pointer;
          flex: 1;
          min-height: 109px;
          overflow: hidden;
          text-overflow: ellipsis;
          .day-number {
            text-align: right;
            padding: 4px 5px 4px 4px;
            opacity: 0;
          }
          &.not-cur-month {
            .day-number {
              color: rgba(0, 0, 0, 0.24);
            }
          }
          .event-box {
            .event-item {
              cursor: pointer;
              font-size: 12px;
              background-color: #c7e6fd;
              margin-bottom: 2px;
              color: rgba(0, 0, 0, 0.87);
              padding: 0 0 0 4px;
              height: 18px;
              line-height: 18px;
              white-space: nowrap;
              overflow: hidden;
              text-overflow: ellipsis;
              &.is-start {
                margin-left: 4px;
                // border-top-left-radius:4px;
                // border-bottom-left-radius:4px;
              }
              &.is-end {
                margin-right: 4px;
                // border-top-right-radius:4px;
                // border-bottom-right-radius:4px;
              }
              &.is-opacity {
                opacity: 0;
              }
            }
            .more-link {
              cursor: pointer;
              // text-align: right;
              padding-left: 8px;
              padding-right: 2px;
              color: rgba(0, 0, 0, 0.38);
              font-size: 14px;
            }
          }
        }
      }
    }
    .more-events {
      position: absolute;
      width: 150px;
      z-index: 2;
      border: 1px solid #eee;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.15);
      .more-header {
        background-color: #eee;
        padding: 5px;
        display: flex;
        align-items: center;
        font-size: 14px;
        .title {
          flex: 1;
        }
        .close {
          margin-right: 2px;
          cursor: pointer;
          font-size: 16px;
        }
      }
      .more-body {
        height: 140px;
        overflow: hidden;
        .body-list {
          height: 120px;
          padding: 5px;
          overflow: auto;
          background-color: #fff;
          .body-item {
            cursor: pointer;
            font-size: 12px;
            background-color: #c7e6fd;
            margin-bottom: 2px;
            color: rgba(0, 0, 0, 0.87);
            padding: 0 0 0 4px;
            height: 18px;
            line-height: 18px;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
          }
        }
      }
    }
  }
}
</style>
